Hi John, * John Cagle <jcagle@xxxxxxxxx> wrote: > Is your iSCSI target also in a virtual machine? If so, maybe the > hypervisor (vmware? kvm?) is caching the 10GB volume that is being > used by the iSCSI target? thanks for answering. No hypervisor involved on the iSCSI target, it's an oldish Infortrend storage [1] for which I am trying to determine the performance profile. Anything else along the stack that might skew the test results? Just to make sure my understanding is correct: - direct=1 should mitigate (disable?) OS caching effects - sync=1, iodepth=1 should make sure that an I/O has really made it to disk before the next on is issued, i.e. should de-facto disable I/O coalescing or device caching Are these sane/valid assumptions? Sebastian [1] http://www.infortrend.com/main/2_product/es_a16e-g2130-4.asp -- To unsubscribe from this list: send the line "unsubscribe fio" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
